Tribology mechanical testing includes the investigation of mechanical properties of materials. At the submicron scale (e.g., nano scale), subjects are viewed with a variety of microscopes including transmission electron microscopes (TEM), scanning electron microscopes (SEM) and the like. The subjects are tested mechanically to observe and determine the mechanical properties of the subjects. In some examples, mechanical testing includes moving a probe in one or more of lateral and normal directions relative to the subject. For instance, a probe indents the subject or laterally scratches across the subject and an attached transducer determines one or more of a variety of mechanical properties including elastic modulus and hardness of the subject material.
The probes used are oriented, in at least some designs, horizontally relative to gravity and a vertical electron source. Further, the probes extend horizontally from an actuator to facilitate engagement with a subject and measurement of the mechanical properties. The length of the probe and its stiffness negatively impact the accuracy of the probe for testing of mechanical properties. In some examples, the transducer attached to the probe experiences large amounts of tip displacement noise proportional to the length of the probe. Additionally, the transducer experiences large tip offset from true horizontal because of gravity. The tip offset is proportional to the stiffness of the probe as well as its length. Tip offset caused by gravity creates an uneven gap between capacitor plates within the transducer and negatively affects the ability of transducer circuitry to accurately measure actual mechanical movement of the probe during testing. For example, the uneven gap between plates saturates a circuit board sensing range thereby providing inaccurate measurements of lateral movement.